Option to compile to /es6/ instead of /lib/ paths

Just an idea.  I wonder if it'd be useful to support the option of compiling imports to `/es6/` instead of `/lib/` paths, if you are working in a recent version of Webpack, or another environment that can load ES6 compatible code.

Maybe a plugin option?

```json5
// .babelrc
{
  "plugins": [
    ["babel-plugin-recharts", { "es6": true }]
  }
}
```